High density optical recordable medium and method for recording

Abstract

An optical recording medium having a recording layer containing an organic colorant as the main component, whereby recording is carried out by changing the reflectivity by irradiation of a laser beam for recording having a wavelength of at most 700 nm, wherein when a light having substantially the same wavelength as the laser beam for recording and having an intensity selected from a range of from 1 to 4.5 mW and a pulse length of about 382 nsec, is irradiated while moving a portion to be irradiated of the medium at a relative velocity of 0.3 m/s to the light, the time required for the reflectivity to change and reach a saturated level, is at most 130% of said pulse length.

What is claimed is:  
     
       1. An optical recording medium having a recording layer containing an organic colorant as the main component, whereby recording is carried out by changing the reflectivity by irradiation of a laser beam for recording having a wavelength of at most 700 nm, wherein when a light having substantially the same wavelength as the laser beam for recording and having an intensity selected from a range of from 1 to 4.5 mW and a pulse length of about 382 nsec, is irradiated while moving a portion to be irradiated of the medium at a relative velocity of 0.3 m/s to the light, the time required for the reflectivity to change and reach a saturated level, is at most 130% of said pulse length. 
     
     
       2. The optical recording medium according to claim  1 , wherein the time required for the reflectivity to change and reach a saturated level, is at most 100% of said pulse length. 
     
     
       3. The optical recording medium according to claim  1 , which has a resin substrate or a resin layer in contact with the recording layer. 
     
     
       4. The optical recording medium according to claim  1 , wherein a guide groove having a groove width of from 0.2 to 0.4 μm is formed. 
     
     
       5. The optical recording medium according to claim  1 , wherein a guide groove having a groove depth of from 100 to 180 nm is formed. 
     
     
       6. The optical recording medium according to claim  1 , which has a reflective layer. 
     
     
       7. The optical recording medium according to claim  6 , which has a protective layer on the reflective layer. 
     
     
       8. An optical recording medium having a recording layer containing an organic colorant as the main component, whereby recording is carried out by changing the reflectivity by irradiation of a laser beam for recording having a wavelength of at most 700 nm, wherein when a light having a wavelength of about 635 nm and having an intensity selected from a range of from 1 to 4.5 mW and a pulse length of about 382 nsec, is irradiated while moving a portion to be irradiated of the medium at a relative velocity of 0.3 m/s to the light, the time required for the reflectivity to change and reach a saturated level, is at most 130% of said pulse length. 
     
     
       9. The optical recording medium according to claim  8 , wherein the time required for the reflectivity to change and reach a saturated level, is at most 100% of said pulse length. 
     
     
       10. The optical recording medium according to claim  8 , which has a resin substrate or a resin layer, in contact with the recording layer. 
     
     
       11. The optical recording medium according to claim  8 , wherein a guide groove having a groove width of from 0.2 to 0.4 μm is formed. 
     
     
       12. The optical recording medium according to claim  8 , wherein a guide groove having a groove depth of from 100 to 180 nm is formed. 
     
     
       13. The optical recording medium according to claim  8 , which has a reflective layer. 
     
     
       14. The optical recording medium according to claim  13 , which has a protective layer on the reflective layer.